Die-cast cylinder block



June 30, 1942, F. 'r. IRGENs l DIE CAST CYLINDER' BLOCK Original Filed Aug. l2, 1939 3 Sheets-Sheet l INVENTOR F/'N/v 7T /Pe-E/v B M, Ma/fm ATTORN EY,

June 30, 1942.

F. T. IRGENS DIE CAST CYLINDER' BLOCK 3 SheelZS-SheerI 2 Original Filed Aug. l2, 1939 ATTORNEY.

June 30,y 1942. F. T. IRGENs DIE CAST CYLINDER'BLOGK Original Filed Aug. l2, 1939 3 Sheets-Sheet 3 INVENTOR /T//wv 7T 66E/v m, JMU

ATTORNEYJ.

Patented June 3(1), 1942 DIE-CAST CYLINDER BLOCK Finn T. Irgens, Wauwatosa, Wis., assignor to Outboard Marine & Manufacturing Company, Milwaukee,^Wis., a corporation of Delaware Original application August 12, 1939, Serial No. 289,746. Divided and this application June 7, 1941, Serial No. 397,019

(Cl. 12S-173) 7 Claims.

This invention relates to the internal combustion art, and has particular reference to improvements in a die cast cylinder block. The present application is a division of my prior application entitled Engine cylinders and method of production, led August 12, 1939, Serial No. 289,746.

Primary objects of the invention are to provide a novel and improved cylinder structure which permits reducing the expense of manufacture, assures against corrosion in the cylinder Water passages and the passagesof the mufiler or exhaust manifold requiring cooling; renders the cooling more effective, particularly enabling the predetermined direction of the cooling water in the art upon inspection of the following dsi closure of the invention.

In the drawings:

Figure 1 is a View in axial section through a single cylinder engine block made in accordance with the invention.

Figure 2 is a view of the block as it appears in side elevation.

Figure 3 is a view of the block taken in section on the line 3-3 of Figure 1.

Figure 4 is a view of the block take-n in section on the line 4 4 of Figure l.

Figure 5 is a plan view of the pre-formed coil used to constitute a Water passage.

Figure 6 is a side elevation of the coil.

Figure 7 is a. view, partially in side elevation and partially in axial section, through a twocylinder engine block of modified design made in accordance with my invention.

Figure 8 is a side elevation of the block shown in Figure '7.

Figure 9 is a view taken in section on the line 9--9 of Figure '7.

Figure 10 is a view of the block shown in Figure 8 as seen from the under side with a manifold casting applied thereto.

Figure 11 is a View taken in section on the line II-I I of Figure 8 and extended to show the manifold casting applied to the block.

Figure 12 is a view of the manifold casting in plan.

Figure 13 is a view of thevmanifold casting in side elevation.

Like parts are identified by the same reference characters throughout the several views.

The present invention relates to the structural features of my novel and improved cylinder and while the method of producing the same is recited herein, claims for said method are being prosecuted in the parent application identified in the preamble above.

The engine in which the invention is embodied as illustrated in Figures A1 to 6, inclusive, is a single cylinder, two-port engine of the type in which the carburetor or mixing valve is provided with a check valve controlling mixture inlet to the crank case, so that the piston only controls the transfer of mixture to the combustion cylinder and the release of the burned gases from the vcylinder to the exhaust.

- The engine in which the invention is embodied as illustrated in Figures 7 to 13, inclusive, is a multi-cylinder engine, which, as shown, has two cylinders of the three-port type, the arrangement being such that the piston controls the admission of combustible mixture to the crank case, and also controls its transfer from the crank case to the combustion cylinder, and also controls the escape of burned gases from the combustion chamber to the exhaust.- Those skilled in the art will recognize that both engines illustrated are of the two-cycletype. A

It will be understood that the devices chosen to exemplify the invention are merely illustrative of its many applications.

In each of my engines the cylinder sleeve and the water passage are preferably pre-formed and cast into place in a die cast cylinder block. The single cylinder block I5 is preferably made of some extremely light material, such'as an aluminum alloy, in which a wear resistant sleeve I6 of some material such as steel has been cast. Preliminary to the casting operation, a preformed helix II of copper tubing or the like is positioned about the sleeve I6 so that upon the conclusion of the die casting operation the tube I'I will be embedded in the aluminum alloy as a conduit for cooling water. The terminal ends I8 and I9 of the tube I1 are brought out to the finished face 20 of the die casting, where they serve to .receive the water supply and discharge connections in the usual way.

Cored into the die casting are the transfer port 2| and the exhaust passage 22, best shown in Figures 1 and 4. Upon the conclusion of the die casting operation the cylinder block is placed in a jig, or is otherwise supported, while parallel drills are used at an oblique angle to bore into the block and sleeve to provide the transfer ports 23 and the exhaust ports 24. The angularity at which these holes are bored locates the transfer ports at a lower level with reference to the direction of piston travel than the exhaust ports, thus giving the correct timing.

The completed' engine cylinder, is extremely light in weight and is manufactured with unusual economy and operates with unusual effectiveness, in that the water passage has no dead spots, but is of uniform cross section throughout, carrying the cooling water exactly where most needed to promote most efficient cooling, and promoting a very efficient heat transfer because the highly conductive aluminum alloy is bonded both to the steel sleeve I6 and to the highly conductive helical tube I1 constituting the water passage.

In the construction shown in Figures 7 to 13, inclusive, the cylinder block 25 is die cast about two cylinder sleeves 26 and a water coil 21, which is not a true helix, but has the peculiar form clearly shown in Figures 7, 9 and 10. In plan, the water coil has something the outline ofthe link of a chain. In elevation, the runs of pipe comprising its sides are straight and parallel, as shown in Figure 7, the entire pitch being provided at the ends of the coil as shown in Figure 10, and indicated in Figure 9 by the plane in which the coil is intersected in that view. One end of the tube comprising the coil 21 is brought out at the crank case end of the casting, as indicated at 28 in Figures 7, 8 and 10. -This is preferably the inlet end. The discharge or return end of the coil 29 is brought out to the finish face 30, as best shown in Figures 8 and 10. Whereas, in the construction shown in Figures 1 to 6, the coil is illustrated as being applied directly about the cylinder sleeve I5, the construction exemplifying the invention in Figures 7 to 11 is such that the coil is spaced slightly from the cylinder sleeve, leaving an intervening film of the die cast metal comprising the block. Either method is satisfactory, and in either instance the die 4casting bonds the coil and the sleeve for effective heat transfer.

In the two-cylinder engine the transfer port is provided at 3l by a recess cored into the die casting and covered by a closure plate 3|0 as indicated in Figure 11. 'I'he exhaust passage comprises a recess 32 cored into the cylinder block within the finish surface 30 and opening to the end of the block, as shown in Figure 10. The inlet manifold comprises another passage within the finish surface 30, as indicated at 33 in Figures 8 and 11. The respective passages 32 and 33 are preferably enlarged by a casting 35 which comprises a muflier and manifold tting provided internally, with a recess 36 registering with recess 32 and a recess 31 registering with recess 33 of the cylinder block. The latter recess communicates with the carburetor inlet indicated at 33, the carburetor not being shown. The recess 36 constitutes a muilier or expansion chamber and has no outlet except through the opening at the side of the cylinder block, as shown in Figure This part of the manifold fitting is preferably water cooled, and for this purpose a length of tubing 40 is embedded in the manifold fitting 35, as shown in Figures 11, 12, and 13, this length of tubing being die cast into the casting 35 and provided with one end 4I which registers with the outlet end 29 of the cylinder jacket tube 21. For convenience in the die casting operation, the other end 42 of the tubing is brought out parallel to the end 4|, but is seated against an imperforate boss 43 of the cylinder casting which is shown in Figure 8.

The water is brought out at the desired point by boring into the manifold casting 35 at one end to provide a hole 44 which penetrates and intersects the tube 40, as best shown in Figures 12 and 13.

As in the construction first described, this device provides an extremely lightweight 'cylinder block, which, at the same time, is strong and wear resistant by reason of the provision of the sleeve, and which provides the cooling water exactly where needed and assures uniformity of flow without eddy currents by reason of the uniform cross section of the water passage.V 'I'he several mix'ture inlet ports 45, transfer ports 45, and exhaust ports 41 are drilled through the block and the sleeve cast therein by drills which enter through the respective recesses 33, 3l and 32.

I claim:

1. A cylinder comprising a sleeve, a tube wound about said sleeve adjacent one end, a casting having one end portion embedding the sleeve and tube and providing a head closing the sleeve at said end, the tube having inlet and outlet openings through the casting to permit water circulation and the other end portion of said casting being provided with mixture admission and gas discharge means, and said casting and sleeve having ports affording communication with said means from the interior of said sleeve.

2. A cylinder comprising a sleeve, a helical tube wound about the sleeve adjacent one end with inlet and outlet end portions outturned, a casting in which said sleeve and intermediate portions of the tube are embedded and bonded. said casting being extended across said sleeve at said end to provide a cylinder head, and said casting being provided, beyond said tube, with a transfer passage opening to its opposite end and associated ports affording communication from said passage to the interior of the sleeve.

3. A cylinder block comprising the combination with a pair of spaced parallel cylinder sleeves, of a water jacket tube encircling the space occupied by associated end portions of said sleeves, said block embedding the tube and associated end portions of the sleeves and providing an exhaust recess opening to two sides of said block andan inlet recess opening to one of said sides, a closure for said last mentioned side provided with recesses registering with the exhaust and inlet recesses of said block, and a water circulation tube embedded in the closure and provided at one end with a portion registering with one end of the water circulation tube embedded in said block.v

4. A cylinder comprising a sleeve, a water tube extending circuitously about the sleeve adjacent one end thereof and free of other portions of the sleeve, a casting in which the sleeve and tube are embedded and bonded, said casting being extended across the sleeve at said end to provide a cylinder head closure and being provided adjacent the portions of said sleeve not 5. A cylinder comprising a heat conductive sleeve, a conduit o heat conductive material encircling one end thereof in contiguous engagement with the outer sleeve wall, a casting enclosing the sleeve and the coolant conduit in bonded relation thereto, said casting extending over one end of the sleeve to provide a closure therefor, a transfer passage extending from the unenclosed end of the casting to a point adjacent the conduit, a chamber provided in the casting at a position opposite said transfer passage.

said casting and sleeve having registering ports leading from the inner end of the transfer passage and from the chamber, respectively, to the interior of the sleeve.

6, A device as set forth in claim 5 wherein said aligned ports are aligned in respect'to an axis obliquely intersecting the sleeve.

7. A cylinder block for an internal combustion engine, comprising a plurality of spaced parallel sleeves, a tube wound about thespace occupied by the firing end portions of the sleeves in the form of a flattened elliptical helix with inlet and outlet end portions extended, a casting extending between and about the sleeves with one portion embedding and bonded to the tube and the portions of the sleeves which it encircles, said casting having another portion provided with inlet, exhaust and transfer recesses and registering ports in the casting and sleeves aiording communication between the respective recesses and the interior of thesleeves.

FINN T. IRGENS. 

